(a) Technical Field
The present invention relates to a system and method of driving a hybrid vehicle, and more particularly, to a method of controlling a fail-safe with respect to problems of an engine clutch.
(b) Background Art
Generally, a Hybrid Electric Vehicle (HEV) is classified into a parallel type and a power split type wherein the parallel type is divided into a Flywheel Mounted Electric Device (FMED) type and a Transmission Mounted Electric Device (TMED) type depending on the location of a clutch. Particularly, for a TMED type hybrid vehicle, an engine clutch is disposed between an engine and a motor and the engine clutch is connected to drive the engine when the motor does not cover the power required by a driver, thereby meeting the power required by the driver.
A known control method of a hybrid vehicle that has a motor integrated typed-transmission, integrally includes a motor for driving a vehicle, a clutch and an engine are sequentially disposed, wherein the motor for driving a vehicle is connected to the engine and the motor integrated typed-transmission is not able to implement a neutral state includes: determining whether driving in an electric vehicle mode is possible when the vehicle is turned on; outputting an engine on signal when driving on an electric vehicle mode not impossible; decoupling the clutch when the engine on signal is output; driving the motor to turn on and increase engine speed when the decoupling of the clutch is completed; turning on the engine by injecting fuel and igniting the engine when the engine speed reaches a predetermined value through rotational force of the motor; and starting a vehicle by coupling the clutch when the engine is turned on.
However, when the engine is driven by coupling the engine clutch while power is provided by only a motor, the engine and a shaft of the motor have to be synchronized and coupled since impact or vibration may be produced. At this time, when remaining hydraulic pressure is produced in the engine clutch, the engine clutch may not be coupled smoothly and the impact due to the driving of the engine may be transferred to a driving shaft through the engine clutch, thereby providing an unpleasant feeling to a driver.
The description provided above as a related art of the present invention is merely for helping in understanding the background of the present invention and should not be construed as being included in the related art known by those skilled in the art.